Fig. 2.

MMP-9 was involved in MCP-1-mediated osteosarcoma migration. a MMP-1, MMP-2, MMP-3, MMP-7, MMP-9, MMP-12, and MMP-13 mRNA expression were measured after 10 ng/mL MCP-1 for 24 h stimulation through a qPCR assay. b MMP-9 mRNA expression was measured in the MG63, U-2OS, and HOS cells after stimulation with different concentrations of MCP-1 (1, 5, 10, and 50 ng/mL) for 24 h. c MMP-2, MMP-3, MMP-9, MMP-12, and MMP-13 expression were observed with stimulation at different concentrations of MCP-1 (1, 5, 10, and 50 ng/mL) for 24 h through a Western blotting assay. d MG-63 cells were treated with control and MMP-9 mAb for 30 min, and cell migration ability was measured with MCP-1 (10 ng/mL) for 24 h stimulation. e MMP-9 inhibitor (SB-3TC; 10 μM) was added to the MG63 cells, and cell migration ability was measured with MCP-1 (10 ng/mL) for 24 h stimulation. f-g Control and MMP-9 siRNA were first transfected into the MG63 cells and incubated for 24 h, MMP-9 protein expression and cell migration ability were measured with or without MCP-1 stimulation. Results are expressed as mean ± SEM, n = 4. *p < 0.05 compared with control, IgG or control siRNA groups; #p < 0.05 compared with the MCP-1-treated group